Statistics Collecting Data Unit

• a

• b

• c

• d

• e

• The graduates who did not respond caused the assumption of independence to be invalid.

• The graduates who did not respond changed the survey from a census to a simple random sample of graduates.

• The graduates who did not respond reduced the sample size and smaller samples are more biased than large samples.

• The graduates who did not respond may represent a group that is homogeneous with respect to income and differs from the graduates who did respond.

• The graduates who did not respond may represent a group that is heterogeneous with respect to income and is similar to the graduates who did respond.

A large company wants to conduct a survey to determine the proportion of its male employees who practice yoga on a daily basis. Two of its regional offices are chosen at random and all of the male employees at each office are surveyed. The plan is an example of which type of sampling?

• Cluster

• Convenience

• Simple random

• Stratified random

• Systematic

In a certain school, students can choose whether to eat in the school’s cafeteria. A reporter working for the school’s newspaper polled students on their reactions to changes in the menu at the cafeteria. For each student leaving the cafeteria in one 20-minute time period, the reporter used a die to determine whether to stop the student and ask how he or she felt about the new menu. In the reporter’s article it was stated that a random sample of the students showed that 23% of the school’s student population was happy with the new menu. Which of the following statements is true?

• Because each student leaving the cafeteria was randomly selected and could choose to answer or not, this is a random sample of the student population, and the 23% is an accurate measurement of the school population’s view of the new menu.

• Because students self-selected whether to eat in the cafeteria, the sampling method might be biased and the sample might not be representative of all students in the school.

• The survey would have been more effective if the reporter had collected the data in one 10-minute time period rather than in one 20-minute time period.

• The survey would have been more effective if students who cared about the food could have called the reporter to tell how they felt about the new menu, so that only students with opinions on the subject would have been surveyed.

• Because no treatment was imposed on the students eating in the cafeteria, one cannot make any conclusions about the new menu.

A _______ is a subset of individuals in the population from which we actually collect data.

• experiment

• sample

• population

• survey

Identify the Population:
Wicomico County Public Schools randomly selected 230 teachers to find out which technology resource it's teachers feel is the most effective.

• 230 Teachers

• All Wicomico County Teachers

• Students

• Wicomico County Public Schools

Why do we use samples instead of the population?

• it is less expensive

• it is easier

• it takes less time

• all of the above

• a

• b

• c

• d

• e

_________ is a sample in which each individual or object in the entire population has an equal chance of being selected.

• Sample

• Population

• Random Sample

• Quartile

• a successful experiment due to the peppermint treatment.

• poor design due to the lack of a control group.

• measurement bias since we do not know the difficulty level of the exam.

• the placebo effect due to the increase of scores in the non-peppermint group.

• blocking by peppermint and no peppermint candy.